Rose leaves - Knowledgebase Question

Los Angeles, Ca
Avatar for lindaandleo
Question by lindaandleo
May 27, 2007
The position presently being held is ground keeper around a few apartment buildings, which is a long way from being a expert gardener.
This morning thought I would take a turn in cultivating or preparing the soil around a few roses, allowing a distance between the roses roots and a ditch to place fertilizer around the rose bush. In doing so, noticed a couple bushes either had holes in their leaves or the green part of the leaf was turning yellow.
Quesstion: Is this caused by lack of fertilizing for the leaves to be turning yellowish?
The leaves with the holes in them, assuming insects and needs a good spray, and can you recommend one?


Image
Answer from NGA
May 27, 2007
I'll bet with a little more experience, you'll become an expert! Here are some basic guidelines for growing a healthy, productive rose plant, whether grown singularly or in a rose garden.

1. Plenty of Sunshine: This is the first and foremost ingredient. When planning your garden, keep in mind that roses like full sun.

2. Rich, loose soil: Roses require a lot of food and nutrients. When planting roses, make sure to mix in generous portions of compost and manure into the native garden soil. If this is not available, add store bought peat moss and cow manure.

3. Provide plenty of nutrients: Roses consume significant amounts of nutrients. What you add to your soil will get them off to a great start, but they will favorably respond to additional fertilizer added year after year.

Did you know the middle number in common fertilizer is Phosphorus. This is the chemical element in the plant world that promotes flower blooming. When growing flowers, a fertilizer heavy in phosphorus will help promote those big, beautiful blooms that growers seek. Most garden stores will have several varieties of fertilizers and ones specifically for roses. When you read the ingredients, you will see the higher phosphorus levels.

Fertilize on a regular basis. We recommend every two to three weeks. Follow the directions on the fertilizer box or bag. Use a higher nitrogen fertilizer at the beginning of the season to promote growth of leaves and roots. Switch over to higher phosphorus as the first buds begin to appear.

4. Pour on the Water: Roses like lots of water. This does not mean they like to get their feet wet. As mentioned above, they like loose soil, which drains well. The right amount of moisture held in the soil compliments of the compost you provide. Adjust your watering to add more for sandy soils, and less for clay soil.

We also recommend you water at the base of the plant and avoid getting the leaves wet. Hot humid weather is a breeding ground for rose diseases. Adding water to the leaves during humid weather will help promote disease. In addition, if you have applied insecticide or fungicides, you are washing it away.

5. Mulch for Weed Control: Do not let weeds ruin the beauty of your rose garden. In addition to "stealing the show", weeds will rob your rose bush of water and nutrients. Avoid this by applying a heavy layer of mulch. Organic mulches are preferred as they will convert over time to compost, further enriching your soil. You can add several inches, effectively blocking but all but the most persistent of weeds. Or, you can lay down black plastic, then add a lighter lay of mulch.

6. Prune and trim: A rose bush will also respond favorably to a good manicure. Prune your bush on a regular basis. A well maintained bush has a full, yet not shaggy appearance. Allow several main stems to grow and develop. Allow enough room between the stems for good air circulation. This will help to avoid plant diseases. It will also cause the plant to focus it's energies on the remaining stems, rewarding you with bigger rose blooms.

7. Guard against insects and disease: Roses are susceptible to both insects and disease. Make sure you know the signs and the treatment.

The most common insect pest of rose bushes are aphids, followed closely by beetles. Fortunately, you can effectively treat and guard against both of these pests. Early and regular treatment is recommended. Don't wait until pests have taken up residence on the rose bush, or in the flower.

Aphids and other sucking insects are a very common problem. They attach themselves to the stem and the top and bottom of leaves. They suck in the juices from the plant, weakening it and leaving it open to disease. They quickly multiply into an unsightly mass if untreated, and you will not want to cut the flower and bring it indoors.

Aphids and most other sucking insects are easily treated. There are also a variety of insecticides that will effectively eliminate this problem. Organic gardeners use insecticidal soaps. A wide range of insecticides and insecticidal soaps can be purchased at a garden store or made at home.

Beetles are the second most common enemy of your rose bush. Japanese beetles are the most common. They like to harbor the flower and can quickly destroy it. Once you have spotted them, it is too late for that particular bloom.

Apply Malathion, Diazinon or other insecticides at the first sign of these pests and on a regular basis.

For organic control of Japanese Beetles, garlic plants are believed to ward them off. Plant Garlic as a companion plant near the bushes. Garlic sprays will also deter them.

Plenty of other insects like your rose bushes as much as you do. Most of them are effectively treated with insecticides. There are "systematic" insecticides that the plant absorbs into it's system, and will provide effective protection for several weeks.

Hope this answers all your questions about growing roses!


You must be signed in before you can post questions or answers. Click here to join!

« Return to the Garden Knowledgebase Homepage

Member Login:

( No account? Join now! )

Today's site banner is by Zoia and is called "Snow White, Deep Green"

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.